Schengen tourist visa after student visa

My daughter (US citizen) is studying in the Czech Republic on a long stay visa. After her visa expires she wants to travel in Schengen area countries for 2 weeks. Would she be able to activate the Schengen 90 day visa if she is leaving 1 Schengen country for another? For example if she travels to Hungary could she ask to go through passport control to activate tourist visa or doe she have to leave the Schengen area?